Restrict listView Items from duplicating

Question

I have a problem dealing with the duplication of my ListView. As you can see on the screenshot, I have a spinner that contains all of the items needed. when the user clicks that specific item, it will add on my ListView. but the problem is the data being duplicated.

This is the Image:

SCENARIO: pretend this is the list items

A

B

C

D

If I click "A". It will add on my ListView right?. and click "B". so the data on my ListView is: A and B. If I click again "A", It will add which it has the current Item on my ListView. I need to restrict the duplication that is happening right now.

This is the code when I click my Spinner

 public void addViolationListenerOnSpinnerItemSelection() {
    spinner_violation.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override

        public void onItemSelected(AdapterView<?> parent2, View view, int position2, long id) {

            if (position2 != 0) {

                vio_val = String.valueOf(spinner_violation.getSelectedItem());
                adapter = new ViolationAdapter(getContext(), generateData());

                lv_inspector_violation.setAdapter(adapter);
                adapter.notifyDataSetChanged();
            }

        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });
}

this is the generateData()

private ArrayList<InspectorViolationItem> generateData() {
    items.add(new InspectorViolationItem(emp_val, vio_val));
    HashSet<InspectorViolationItem> hs = new HashSet<>();
    hs.addAll(items);
    items.clear();
    items.addAll(hs);
    return items;
}

the InspectorViolationItem is just a Getters and Setters so I think that don't need to post the code.

And lastly, This the Adapter that I've used:

public class ViolationAdapter extends ArrayAdapter<InspectorViolationItem> {

Context c;

private ArrayList<InspectorViolationItem> itemsArrayList;


public ViolationAdapter( Context context, ArrayList<InspectorViolationItem> itemsArrayList) {
    super(context, R.layout.item_violation, itemsArrayList);
    this.c = context;
    this.itemsArrayList = itemsArrayList;

}


@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    // 1. Create inflater
    LayoutInflater inflater = (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    // 2. Get rowView from inflater
    View rowView = inflater.inflate(R.layout.item_violation, parent, false);

    // 3. Get the two text view from the rowView
    TextView labelView = (TextView) rowView.findViewById(R.id.txt_violation_employee);
    TextView valueView = (TextView) rowView.findViewById(R.id.txt_violation_violation);



    // 4. Set the text for textView
    labelView.setText(itemsArrayList.get(position).getEmployee());
    valueView.setText(itemsArrayList.get(position).getViolation());

    // 5. retrn rowView
    return rowView;
    }

}

While adding that model data into ArrayList check, If that model does not contain into ArrayList then add the data. — ॐ Rakesh Kumar, Oct 04 '18 at 03:55

score 0 · Accepted Answer · answered Oct 05 '18 at 03:12

I have done it by putting the selected items on ArrayList<>

and make the validations like this:

 if (position2 != 0) {
                vio_val = String.valueOf(spinner_violation.getSelectedItem());

                if (!violationHolder.contains(vio_val)) {
                    adapter = new ViolationAdapter(getContext(), generateData());
                    violationHolder.add(vio_val);

                    lv_inspector_violation.setAdapter(adapter);
                    adapter.notifyDataSetChanged();
                } else {
                    Toast toast = Toast.makeText(getContext(), "Duplicate Violation.", Toast.LENGTH_SHORT);
                    toast.setGravity(Gravity.CENTER, 0, 0);
                    toast.show();
                }
            }

Thanks for your help

Restrict listView Items from duplicating

1 Answers1